The BRNKL key fob receiver requires a connection to +12V and Ground. Ensure that the key fob receiver is not connected to a +24V connection.
The white wire from the BRNKL key fob receiver can be connected to one of pins 4 through 7.
When configuring your BRNKL app, ensure that you select "Key Fob Attached" on the Digital Input that you have wired to. For example, if you connect the white wire from the key fob receiver to Pin 4, ensure that you enable "Key Fob Attached" on Digital 1.
If a Siren or Lights are connected to one of the outputs (Pin 2 or 3), ensure that you enable "Output on Alert" to either Output 1 or Output 2 so that your key fob triggers the siren or lights to flash on and off when arming or disarming the system.
Below is a screenshot from the app with a Key Fob configured and connected to Input 1 (Pin 4) and a Siren connected to Output 1 (Pin 2) on the BRNKL connector.